Lighting WPG clarification

[loyalrogue]

I've read several recommendations for wpg lighting guidlines for a reef tank.
I just purchased some 50/50 compact fluorescent bulbs and I noticed on the packaging it states that a 20w bulb outputs 100w of light.
When figuring wpg do I use the 20w of power it draws or the 100w of light it outputs?
It would seem logical to use the output value but I thought I would ask here first.
Thanks.

 

[Marc118]

I wouldnt trust that. If its a 20w light thats what your getting.

What size is the tank? What to you plan on stocking it with? Any coral down the line?

 

[roka64]

I agree, if it is a 20W bulb, it would only put out 20W...I think...
Does it say something like this:
50% natural daylight 6000K.
50% actinic 03 blue.
The lamp equals a 100 watt incandescent lamp

is this it?

http://www.aquariumguys.com/minicompact3.html

 

[ianrich147]

definatly only 20w

 

[tecwzrd]

Tank height also has to be taken into consideration versus gal per watt solely. i.e.: a 30 gal high which is 24” high with PC or VHO lighting of 260W gives you 8.6 WPG but still may not be enough to house high light corals. Positioning of high/low light corals is key also with lower light corals closer to the sand and high light corals placed up high.

Is this light just to light the tank or were you considering corals?

 

[loyalrogue]

Does it say something like this:
50% natural daylight 6000K.
50% actinic 03 blue.
The lamp equals a 100 watt incandescent lamp

is this it?

http://www.aquariumguys.com/minicompact3.html

Yep. That's exactly what it says.

And it's a standard 10g tank w a RIO 180 ph which I'll be putting some coral in, probably some xenia, zoos, ricordia or mushrooms.
Haven't decided yet.

Right now it has two of those 50/50 bulbs listed above.
Any advice?

 

[roka64]

I don't have any experience in coral, other than SCUBA. It will depend on your tank, as Tec said.

I put my current tank's specs, and critters and equipment in "my info" button, so folks have an idea of what I have....

 

[AMANIQU77]

I've never used that type of bulb before. Sorry.

But in terms of what specimen you will house, it looks like a good list. In my opinion, however, I'd rather get a compact fluorescent fixture in that way the light is evenly distributed across the tank.

With that said, I've seen some setups in this forum just like yours (open top with that kind of bulb). I hope they can give you tips out there. Might want to rename your subject "Coralife 20W Mini Fluorescent Users" or something.

Good luck!